This invention relates generally to an electrophotographic printing machine, and more particularly concerns an apparatus for stapling sets of copy sheets reproduced from a set of original documents.
Typically, an electrophotographic printing machine may reproduce a plurality of booklets or sets of copies. Each set of copies corresponds to the set of original documents. The copies of each set are secured to one another by a stapling apparatus. The stapling apparatus accepts each set and then drives staples through all of the copy sheets in the set to form finished booklets.
Various types of stapling systems have been devised for use with electrophotographic printing machines. For example, the stapler may be actuated electronically. In this type of a system, the set trips a sensor which then actuates a solenoid for driving the staple therethrough. Alternatively, a hydraulic system may also be employed. In a hydraulic system, a ram, driven hydraulically, drives the staple through the set of sheets. A pneumatic system, which is air actuated, is essentially the same as a hydraulic system with a compressible gas rather than a liquid being employed. Finally, a mechanical system wherein the staple is driven by a driver mechanically actuated, has also hereinbefore been utilized in conjunction with electrophotographic printing machines. In all of the foregoing systems, power is a significant requirement and the reduction thereof highly desirable. Furthermore, the hardware and complexity of the mechanism associated with the stapling system increases the cost of the printing machine. It has been found that a pneumatic system may be the least expensive and complex of the foregoing devices provided that it is designed with a view to minimizing cost and complexity.
Accordingly, it is a primary object of the present invention to improve the stapling apparatus employed in an electrophotographic printing machine.